APPARATUS FOR STORING NOx REDUCTANT ON A VEHICLE

Abstract

Apparatus is disclosed for storing a liquid NO x reductant on a vehicle. The apparatus comprises a container for containing the liquid NO x reductant, a first heating device located in the container and adapted to heat the NO x reductant in use, and a tube that has a first end adapted to be submerged in the liquid NO x reductant in the container in use. The tube is adapted to extract liquid NO x reductant from the container and the tube includes a second heating device extending along at least a portion of the length of the tube that is located within the container.

1 . Apparatus for storing a liquid NO x  reductant on a vehicle, the apparatus comprising:
 a container for containing the liquid NO x  reductant;   a first heating device located in the container and adapted to heat the NO x  reductant in use;   a tube assembly having a first end adapted to be submerged in liquid NO x  reductant in the container in use, and being adapted to extract liquid NO x  reductant from the container, the tube assembly comprising a tube and a second heating device extending along at least a portion of the length of the tube that is located within the container; and   a plate member mechanically coupled to the first heating device and the first end of the tube assembly.   
     
     
         2 . Apparatus according to  claim 1 , wherein the container includes a removable closure and the first and second heating devices are electrically coupled to electrical apparatus outside the container through the removable closure and the tube assembly is fluidly coupled to further apparatus outside the container through the removable closure when the container is closed by the closure. 
     
     
         3 . Apparatus according to  claim 2 , wherein the first heating device and the first end of the tube assembly are mechanically coupled to a plate member that is adapted to be located adjacent the bottom of the container when the container is closed by the closure. 
     
     
         4 . Apparatus according to  claim 1 , wherein the second heating device comprises a helical resistive wire heating device encircling the tube. 
     
     
         5 . Apparatus according to  claim 1 , wherein the second heating device comprises a ribbon heater. 
     
     
         6 . Apparatus according to  claim 1 , wherein the second heating device comprises a flexible resistive heater. 
     
     
         7 . Apparatus according to  claim 1 , wherein the second heating device comprises a film heater circuit. 
     
     
         8 . Apparatus according to  claim 7 , wherein the film heater circuit is printed on the outside surface of the tube. 
     
     
         9 . Apparatus according to  claim 1 , wherein the tube comprises a flexible tube. 
     
     
         10 . Apparatus according to  claim 9 , wherein the second heating device is embedded within the walls of the flexible tube 
     
     
         11 . Apparatus according to  claim 1 , wherein the tube comprises a first substantially rigid tube. 
     
     
         12 . Apparatus according to  claim 11 , wherein the first substantially rigid tube comprises a metal tube and the second heating device is in contact with the external surface of the first substantially rigid tube, so that heat from the second heating device is conducted through the sidewall of the first substantially rigid tube. 
     
     
         13 . Apparatus according to  claim 1 , wherein the tube assembly comprises an outer sheath, and wherein the portion of the tube along which the second heating device ( 11 ;  21 ;  46 ;  40 ) extends is enclosed in the outer sheath. 
     
     
         14 . Apparatus according to  claim 13 , wherein the tube and the outer sheath define a space between the outer surface of the tube and the inner surface of the outer sheath, and the space is plugged at both ends to isolate the second heating device from NO x  reductant in the container, in use. 
     
     
         15 . Apparatus according to  claim 1 , wherein the tube assembly further comprises a temperature sensor and/or a liquid level sensor. 
     
     
         16 . Apparatus according to  claim 1 , wherein the tube has an internal wall defining a channel for extracting liquid NO x  reductant from the container and an external wall, and the second heating device is adapted to heat both the internal wall and the external wall of the tube. 
     
     
         17 . Apparatus according to  claim 1 , wherein the first and second heating devices are independently operable. 
     
     
         18 . An NO x  reductant storage apparatus for a vehicle, the apparatus comprising:
 a container for containing the NO x  reductant;   a first heating device located in the container;   a tube assembly adapted to extract liquid NO x  reductant from the container, the tube assembly comprising a flexible tube and a second heating device extending along at least a portion of the length of the tube; and   a plate member mechanically coupled to the first heating device and the tube assembly and adapted to locate the first heating device within the container at a predetermined position relative to the tube assembly.   
     
     
         19 . The NO x  reductant storage apparatus of  claim 18 , wherein the first heating device is a resistive element coiled heater which is thermally coupled to the plate member. 
     
     
         20 . The NO x  reductant storage apparatus of  claim 18 , wherein the first and second heating devices are independently operable.